1. Field of the Invention
The present invention relates to an improved structure of washing machine specially designed for washing motor vehicles, industrial machines, equipment of food and milk plants, etc. The washing machine greatly saves energy and is practical and durable in use.
2. Description of the Prior Art
FIG. 5 shows a washing machine for washing machines and industrial equipment according to the prior art. This washing machine comprises a boiler 10 connected to a water source and controlled to heat water to the desired temperature, a pump 20 driven by a motor 30 to pump warm water A1 from the boiler 10 to a water supply pipe 50, an unload valve 60 controlled to release water pressure from the water supply pipe 50, a spray gun 40 connected to the output terminal of the water supply pipe 50 and controlled by a lever 4b1 to eject warm water through a nozzle 4a1, and a water return pipe 70 for sending warm water A1 from the water supply pipe 50 back to the boiler 10 when the unload valve 60 is operated. This structure of washing machine has drawbacks. Because tile pump 20 and the motor 30 are kept operating during the operation of the washing machine, much energy is wasted and, the inside pressure of the water supply pipe 50 as well as the pump 20 will be increased rapidly when the spray gun 40 is stopped, causing the metal fittings of the water supply pipe 50 to wear quickly. Furthermore, because the motor 30 must be turned on/off by land, the working efficiency of the washing machine is low.